Abstract
We conducted an idiographic analysis to examine the effect of survey burden, measured by the length of the most recent questionnaire, or number of survey invitations (survey frequency) in a one-year period preceding a new survey, on the response probability to a new survey in a probability-based Internet panel. The individual response process was modeled by a latent Markov chain with questionnaire length and survey frequency as explanatory variables. The individual estimates were obtained using a Monte Carlo based method and then pooled to derive estimates of the overall relationships and to identify specific subgroups whose responses were more likely to be impacted by questionnaire length or survey frequency. The results show an overall positive relationship between questionnaire length and response probability, and no significant relationship between survey frequency and response probability. Further analysis showed that longer questionnaires were more likely to be associated with decreased response rates among racial/ethnic minorities and introverted participants. Frequent surveys were more likely to be associated with decreased response rates among participants with a large household. We discuss the implications for panel management and advocate targeted interventions for the small subgroups whose response probability may be negatively impacted by longer questionnaires or frequent surveys.